In DNA from biopsies, mosaicism for pathogenic variants, including KRASp.Ala146Thr in two OES subjects, FGFR1 p.Asn546Lys and KRAS p.Ala146Val in ECCL patients, and KRAS p.Gly12Asp in both SFMS patients, was demonstrated.
KRAS codon 146 mutations, as well as the previously reported OES-associated alterations, are known oncogenic KRAS mutations with distinct functional consequences.